BZOJ:1816 [Cqoi2010]扑克牌 （贪心或二分答案）

题面

\(solution:\)

\(code:\)

#include<iostream>
#include<cstdio>
#include<iomanip>
#include<algorithm>
#include<cstring>
#include<cstdlib>
#include<ctime>
#include<cmath>
#include<vector>
#include<queue>
#include<map>
#include<set>

#define ll long long
#define db double
#define inf 0x7fffffff
#define min(A,B) (A>B?B:A)
#define rg register int

using namespace std;

struct su{
    int k,v;
}a[55];

int n,m,t,x,ans;

inline int qr(){
    char ch;
    while((ch=getchar())<'0'||ch>'9');
    int res=ch^48;
    while((ch=getchar())>='0'&&ch<='9')
        res=res*10+(ch^48);
    return res;
}

inline bool cmp_v(su x,su y){return x.v<y.v;}

int main(){
    freopen("cards.in","r",stdin);
    freopen("cards.out","w",stdout);
    n=qr(),m=qr();
    for(rg i=1;i<=n;++i)
        a[i].k=i,a[i].v=qr();
    sort(a+1,a+n+1,cmp_v);
    ans=t=a[1].v; a[n+1].v=inf;
    for(rg i=1;i<=n;++i){
        x=(i-1)?min(m/i,t/(i-1)):(m/i);
        x=min(x,a[i+1].v-a[i].v);
        ans+=x,m-=x*i,t-=x*(i-1);
    }printf("%d\n",ans);
    return 0;
}